Bold statement: The fifth starter isn’t just a slot to fill—it’s the hinge on which the Padres’ season may turn, and saying it plainly doesn’t do justice to how tangled and important that role actually is. And this is where the conversation gets complicated but also reveals the real stakes behind a rotation that aims to push a contender into the postseason.
PEORIA, Ariz. — The so-called No. 5 starter in San Diego’s rotation is supposed to be simple in theory, yet it isn’t. The label itself is so vague that it often feels like it doesn’t exist as a concrete position. Padres pitching coach Ruben Niebla framed the goal this way: you want a group of pitchers so interchangeable that you don’t notice the difference between your five and your three, or your three and your one. In other words, deploy a pitcher who can reliably give you length and quality, regardless of the exact slot.
Right now, five pitchers are competing for what is likely a single opening at the back end of the rotation. Inside the organization there’s debate about whether the internal options are ready to anchor a rotation that could lift the team into the playoffs. But the question remains: what will be asked of Walker Buehler, Germán Márquez, Triston McKenzie, Marco Gonzales, or JP Sears, should one of them win the job? And what about Griffin Canning, who would hold the spot if not for an Achilles injury that will sideline him for most, if not all, of April? Then there are possibilities that include Matt Waldron, Jackson Wolf, Miguel Mendez, or perhaps a surprise addition acquired via trade or a quick rise through the minors.
What’s clear is that the “fifth spot” will likely be claimed by multiple players across the season. Previous seasons illustrate this reality: Kyle Hart started last year as the No. 5, moved on and back, and was eventually replaced by different names when injuries and trades shuffled the order. Michael King went down with a shoulder issue, and the fifth spot saw several occupants—from Hart and Stephen Kolek to Ryan Bergert, Waldron, Nestor Cortés, and Sears. In total, ten pitchers started five-plus games, and fourteen threw at least one game in the fifth-slot role last year.
This isn’t unique to the Padres. In 2025, no team had fewer than six pitchers with five or more starts, and many teams leaned on a rotating cast for the fifth starter. Sometimes the fifth starter boasted one of the better ERAs in the rotation, and in a few cases, the fifth starter led the way in starts. The pattern underscores a simple truth: depth and reliability matter more than a flashy label.
Two seasons ago, Waldron — who served as the fifth starter — posted a 2.76 ERA over 14 starts in a stretch that spanned roughly two and a half months. In that period, the rest of the rotation combined for a 4.35 ERA, with only Michael King’s 3.00 ERA approaching Waldron’s success.
Niebla is clear about the expectation for a contending team: your fifth starter must be dependable enough to win games and eat innings. If you’re aiming for a playoff run, you’re not looking for a spark plug; you’re looking for a pitcher who can give you quality outings regularly. If the team isn’t in that top tier, the plan shifts toward developing talent within the system and testing whether minor-league options can assume the role. The Padres, however, consider themselves a top-four playoff contender, so the expectation is that the fifth starter can deliver wins and innings, perhaps not always seven innings like the top three, but enough to keep the team in ballgames.
That’s the ideal, and the pragmatic takeaway is that a contending team needs a bullpen and rotation capable of covering at least five innings while limiting damage. If the Padres’ bullpen proves as dependable as hoped, this depth could be a pivotal ingredient in a season that could push them from a modest projection (about 79 wins, per FanGraphs) toward a third straight 90-win season.
Last season, the Padres were 63-24 when the starter pitched at least five innings and allowed three or fewer runs—a level of success well above the MLB average. The five pitchers who logged fifth-starter starts for San Diego combined for 16 five-or-fewer-run innings starts, with the team going 11-6 in those games.
When you compare apples to apples across teams, the No. 5 starter’s impact varies. The 11 other playoff teams’ fifth starters in 2025 averaged about 21 starts, roughly 109⅓ innings, and a 4.62 ERA, illustrating the wide range of what the role can look like in practice.
San Diego isn’t hunting for an true ace in this group, but they aren’t settling for someone simply to fill a spot. As manager Craig Stammen put it, a fifth starter should feel like the ace on the day they pitch. The mindset is: every time they take the mound, they’re the best option available, and the goal is victory on that day. The role may not demand the same elite talent as the front-end of the rotation, but it does demand the ability to win games and keep the team in contention.
In sum, the Padres’ approach to the fifth starter is less about finding a one-name hero and more about cultivating a reliable, innings-eating contributor who can help stabilize the rotation and support the team’s postseason ambitions. The question remains: which of the current contenders will seize, or share, that crucial responsibility—and how will they redefine what a fifth starter can contribute to a winning season?
